Fatty foods may not be the healthiest diet choice, but those rich in unsaturated fats, such as avocados, nuts, and olive oil, have been found to play a pivotal role in sending this important message to your brain: Stop eating, you're full.

A new study by University of California, Irvine pharmacologists shows that these fats trigger production of a compound in the small intestine that curbs hunger pangs. This discovery, the researchers say, points toward new approaches to treating obesity and other eating disorders.

Daniele Piomelli, the Louise Turner Arnold Chair in Neurosciences, and his colleagues have studied how a fat-derived compound called oleoylethanolamide (OEA) regulates hunger and body weight. In their current work, which recently appeared in Cell Metabolism, they found that an unsaturated fatty acid called oleic acid stimulates production of OEA, which in turn decreases appetite.

Oleic acid is transformed into OEA by cells in the upper region of the small intestine. OEA then finds its way to nerve endings that carry the hunger-curbing message to the brain. There, it activates a brain circuit that increases feelings of fullness. In previous studies, Piomelli found that increasing OEA levels can reduce appetite, produce weight loss, and lower blood cholesterol and triglyceride levels.